add VLCLocalNetworkServiceBrowser protocol
add VLCLocalNetworkServiceBrowser implementations for NSNetBrowser-based discovery

don't convert port number to string and back to number

reduce number of switches with magic numbers
add enum for LocalServerSections
introduce VLCLocalNetworkService as a wrapper around different network services

(cherry picked from commit b5412fce)

(cherry picked from commit f4ed2eb4)

(cherry picked from commit 1e0ecbd7)

(cherry picked from commit e2fcfb7f)

(cherry picked from commit 88c0879e)

(cherry picked from commit 2a5873b9)

(cherry picked from commit 972e48c7)

(cherry picked from commit c94a9578)

(cherry picked from commit b4692d53)

(cherry picked from commit 03a07661)

(cherry picked from commit e7edd115)

Add (preliminary) icons for tvOS App